8 int strncasecmp(const char *s1, const char *s2, size_t n)
10 const unsigned char *c1 = (const unsigned char *)s1;
11 const unsigned char *c2 = (const unsigned char *)s2;
16 /* toupper() expects an unsigned char (implicitly cast to int)
17 as input, and returns an int, which is exactly what we want. */
18 d = toupper(ch = *c1++) - toupper(*c2++);